macbeth was mad in the dagger solilolquy

Macbeth in the scene with the dagger is mad. he shows that in act 2 scene 1 with the imaginary dagger. "art thou not, fatal vision , sensible/ to feeling as to sight? or art though but/ a dagger of the mind, a false creation/ proceeding from the heat-oppressed brain?/ I see there yet, in form as palpable/ as this which now I draw. (2.1 . 36-41). he is crazy because he is thing to grab a dagger that is not there. hence in the scene Macbeth is mad.